SaiPa were looking to prove a point following their 4-2 series loss in the Playoff Finals in May, and they took the lead through new signing Patrik Siikanen, only for a new KalPa addition, Cade Borchardt, and Aleksi Klemetti to turn things around before the end of the first period.
The home side levelled things up midway through the second period through Otto Kivenmaki, and they repeated the feat midway through the third thanks to Henri Nikkanen responding to Filip Westerlund's strike.
But SaiPa wouldn't be able to rely on their equalising abilities in overtime, and so it proved, as Lasse Lappalainen found the net after 01:39 to give the champions a 4-3 victory on opening night.
Lukko finished top of the regular season standings last year before ultimately exiting the Playoffs at the Semi-final stage, but their mission to finish top of the pile this time has already taken a blow after they were beaten 4-1 at home by Tappara this evening.
The visitors did the damage in the second period, in which league debutant Oliver Suvanto, Kasper Simontaival and Otto Rauhala all found the net.
Aarne Intonen threatened a Lukko comeback with his goal with seven minutes to go, but that was officially quashed in the final seconds when Emil Sylvegard found the empty net.
Ilves finished second last season before beating Lukko in the bronze medal game - they also found the going tough this evening, as they lost 4-3 away to JYP.
The hosts finished 14th last season, missing the Playoffs, but made the better start and went ahead courtesy of Juuso Puustinen. Strikes from Matic Torok and Teemu Engberg looked to have put the Tampere side in control, but back came JYP, who equalised through Otto Makinen.
The teams traded goals in the second through Lukas Jasek and Eetu Peltola, but with less than five minutes to play, Sami Vatanen scored the crucial goal that kept the three points in Jyvaskyla.
Finding themselves leading the way after one round are Assat, who cruised to a 5-1 win on the road against KooKoo. Peter Tiivola broke the deadlock early on but it wasn't until the midpoint in the match that Dylan Fabre and Valtteri Lipiainen put the visitors in contol.
Johan Olofsson made it 4-0 and though Oskari Luoto pulled one back almost instantly, Fabre's second of the game killed off any hopes of a KooKoo comeback.
Vaasan Sport's 3-0 win over Karpat gives them an ideal start to the season, while Pelicans - who lost the Playout before salavaging their place in the Liiga for this season against Jokerit in the Relegation Playoff - were the only other side to record an opening night shutout; they beat Kiekko-Espoo 1-0.
From the lowest scoring match, to the highest - HIFK earned themselves a 5-3 victory over Jukurit on the road in Mikkeli.
Finally, the first penalty shootout of the new season went the way of TPS Turku, whose 2-1 victory on penalties earned them a 3-2 win over Hameenlinna away from home.